Telecommunications networks can generally be divided into two components, cellular networks and conventional land-line networks. While the cellular networks support wireless telephone services and the land-line networks support conventional telephone service, the networks and services generally overlap in that a user of a wireless telephone service can place a phone call through the cellular network to the land-line network to thereby establish a telephone link with a conventional telephone, and conversely, a user of a conventional telephone service can place a phone call through the land-line network to the cellular network to thereby establish a phone link with a wireless telephone. Furthermore, in some instances, the cellular network is comprised of communication links that may, at times, be considered part of the land-line network.
There are many cellular networks in place around the United States and the rest of the world. Generally, a cellular network is bounded by a geographic territory. For example, the AT&T cellular network generally services the entire continental United States while the Cellular One cellular network generally services the east coast of the United States. A cellular network is generally comprised of multiple service areas, each of which is subdivided into multiple cells. Each cell has a base station for receiving and transmitting phone calls between a mobile phone and the cell, and the base stations are connected to a switch normally located in a mobile telephone switching office (MTSO). The number of switches required for a service area varies depending on the volume of calls experienced in the service area. Some service areas have only one switch to which all the base stations within the service area are connected; some have multiple switches such that the base stations within the service area are divided between the switches; and some even share a switch with other service areas. The MTSO generally manages the multiple switches in the cellular network and maintains a communications link between the cellular network and the land-line network.
Functionally, when a call is placed by a wireless phone located within a given cell of a service area in the cellular network, the cell base station receives the phone call and forwards it to the service area switch where it is forwarded to the destination device. If the destination device is another wireless phone located in another service area of the same cellular network, the service area switch forwards the phone call to the switch of the destination service area where it is forwarded to the bases station of the destination cell for transmission to the destination wireless phone, thereby establishing a communication link between two wireless phones within the same cellular network. If the destination device is a conventional phone, the MTSO directs the call from the calling service area switch to a switch associated with the land-line network where the call is connected to the conventional phone. If the destination device is a wireless phone located in a different cellular network, the calling service area switch forwards the phone call through the land-line network to the destination cellular network where it is directed through the switch of destination service area to the base station of the destination cell for transmission to the destination phone, thereby establishing a communication link from the calling wireless phone to the destination wireless phone by way of the calling cellular network, the land-line network and the destination cellular network.
One of skill in the art will understand that a phone call initiated by a wireless, phone may involve many different switches in many different networks. Generally, the first switch accessed by the caller is the "billing switch" responsible for tracking and recording all the various charges associated with the phone call, including enhanced services. Such charges might include basic charges, in-network roaming charges, out-of-network roaming charges, land-line fees, long distance fees or other cellular network fees as will be appreciated by one of skill in the art. A billing switch that improperly tracks fees associated with a phone call or with any enhanced services provided by the service provider, results in lost revenue to, or over billing by, the service provider. Therefore, it is critical to the service provider that the billing switches consistently and accurately track and record fees.
Generally, a user of a cellular phone will execute a subscription agreement with one or more service providers which allows the user to place calls within the service providers cellular network. The user generally enters subscription agreements with service providers having cellular networks covering the geographic area in which the user normally makes phone calls. For purposes of this description, the service providers with which the user has a subscription agreement will be referred to as "home" service providers. The various service providers have executed agreements whereby a subscriber to a service provider can use the services of other service providers, subject to a fee, and the "home" service provider will appropriately charge the subscriber.
Every wireless phone contains an Electronic Serial Number (ESN) and a Numbered Assignment Modules (NAMs) which together indicate the "home" service providers to which the phone is associated (hereafter the ESN and the NAM will be collectively referred to as the "NAM"). When a wireless phone establishes a phone call, the associated billing switch recognizes the NAM in order to determine whether the phone is communicating with a "home" or "non-home" service provider in order to properly track and allocate fees. Initiating a call within the network of a "home" service provider will be charged differently than initiating a call within the network of a "non-home" service provider. Furthermore, calls initiated within "non-home" service providers will be charged differently depending upon the specific agreement between the non-home service provider and the home service provider.
Each billing switch tracks and records the fees associated with a phone call through use of a "billing table" that is preprogrammed into the switch by the service provider. The billing table recognizes charges associated with each call including any charges for enhanced services (i.e. call waiting) subscribed to by a user. Generally, the switches will be reprograrmned with updated billing tables at various times including whenever a new service area is added or removed from the cellular network; whenever a subscriber is added or deleted from the service provider; whenever the cellular network fees are changed; whenever the agreement between the cellular network and other networks changes. Furthermore, the hardware and or software of a switch may be periodically upgraded (e.g., a base station may be added to the switches' service area or the switch may be reprogrammed with "upgraded" software for bug fixes or feature enhancements). In addition, the switch undergoes maintenance or routing changes that change or effect the interaction between the switches. The upgrades and maintenance sometimes result in errors associated with billing and network operations causing the switch to malfunction as it processes calls. Whenever the switch is reprogrammed, upgraded, or undergoes maintenance, it is critical that the service provider have an efficient means for verifying that the various switches function properly and correctly track and record fees.
When a call is placed, the numerous switches handling the call are responsible for properly routing and billing the call. A switch that is installed, reprogrammed, upgraded, or maintained improperly may result in improperly routed and/or billed calls and thus lost revenue to the service provider. Because switches are being installed in new networks and because switches in existing networks are continuously reprogrammed, upgraded and/or maintained, a system for testing the proper operation of the numerous switches within a telecommunications network, and thus the proper routing and billing of calls to and from such network, is necessary to maintain an efficient network. Presently, there are two such types of systems available to service providers, one made by Rotodata and the other made by Comarco.
The Comarco system includes a testing device that places a wireless call to a service area of a cellular network where such call is routed through the switch associated with the service area to a destination device whereby a communication link is established between the testing device and the destination device. The destination device may be a mobile or land-line phone offering a pre-recorded audio message that is communicated over the established communications link to the user of the testing device where proper operation of the switch may be confirmed. The testing device may also be equipped with multiple phones such that the testing device may establish a communication link from a first one of said phones to a second one of said phones thereby establishing the testing device as the destination device. The testing device must be located "in the field" (e.g., geographically within the service area) so as to be capable of wireless communication with the service area. One shortfall of the Comarco system is that the testing device is designed to be locally controlled in that setting the parameters of the testing device and/or initiating the test requires a technician to be located "in the field" with the testing device. This limitation also requires that a field technician travel to the various service areas of the cellular network in order to test the numerous switches within the network. Another shortfall of the Comarco System is that the testing device does not have the capability to record audio received from the destination device thereby requiring that a technician be located in the field with the testing device during testing in order for the technician to hear the quality of the audio received at the test device. Yet another shortfall of the Comarco system is that the presence of the technician in the field prevents the technician from accessing the billing; records of the call, which are normally located in a central office, and therefore from verifying proper billing simultaneously with the verification of the call. Still yet another shortfall of the Comarco system is that it cannot complete calls from one testing device to a second testing device. A further shortfall of the Comarco system is that it does not enable the user to verify the audio of the placed call in both directions without a technician being present at each end of the call. Yet a further shortfall of the Comarco system is that it cannot interactively control or measure the testing being performed by the testing device.
The Rotodata system includes a testing device that places a wireless call to a service area of a cellular network where such call is routed through the switch associated with the service area to a destination device. Typically, the destination device is a pre-recorded audio message that is communicated to the user of the testing device to confirm proper operation of the switch. Unlike the Comarco system, the Rotodata system has remote control feature that permits operation of multiple testing devices from a remote location. One shortfall of the Rotodata system is that the remote capability does not permit audio from the testing device to be communicated to the remote control location thereby forcing the user to rely on non-audio information in the call verification process. This limitation prevents the user from remotely verifying whether the audio was received, or the quality of the audio received, at either the testing device or the remote control location and prevents the user from remotely testing services such as 911 emergency service, voice mail, call forwarding, call waiting, no answer transfer and messaging, and any other service that can be verified through an interactive audio process. Accessing the audio requires the user to be in local control of the testing device which requires the technician to be located in the field with the testing device. Another shortfall of the Rotodata system is that the remote capability does not permit audio from the remote control location to be communicated to the testing device or the destination device thereby preventing the user from audio interaction with either of the devices. This limitation also prevents the user from testing services such as voice mail, call forwarding, call waiting, no answer transfer and messaging or any other service that can be verified through an interactive audio process. Yet another shortfall of the Rotodata system is that the remote control is implemented over an unsecured POTS line. Still yet another shortfall of the Rotodata system is that the system does not allow for individual call control of each remote unit. For example, the remote units will accept a 24 hour series of commands to run without master control such that the user will lose 24 hours of test if a test error occurs.
Therefore, an object of the invention is a system for remotely testing a switch of a telecommunications network where audio received at the testing device is communicated to the remote control location whereby the user can verify the proper completion of the call, the audio quality, and the billing records.
Another object of the invention is a system for remotely testing a switch of a telecommunication network where audio from the remote control location is communicated to the testing device.
Yet another object of the invention is a system for remotely testing a switch of a telecommunication network where audio from the remote control location is communicated through the testing device to the destination device.
Still yet another object of the invention is a system for remotely testing a switch of a telecommunications network where such system is capable of centralized remote management of multiple testing devices and centralized remote testing of multiple switches.
A further object of the invention is to provide a system for remotely testing a witch of a telecommunications network where a communication link is established from a first testing device through a switch to a second testing device where the user at a remote control location has access to audio received at the first testing device and the second testing device.